Riveting machine



Feb. l0, 1948. A. F. KOEHLER RIVETING MACHINE Filed June 11, 1943 \f ....u, .......E E!

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Patented Feb. l0, 1948 UNITED STATES PATENT oFFlcE Application J une 11, Il(9(f:4l6,1i-19l)hlo. 490,542

3 Claims. 1

The` present invention relates to new and useful improvements in riveting machines embodying a magazine feed and pneumatic means for operating the riveting hammer.

An important object of the present invention is to provide trigger controlled pneumatic means for successively moving the rivets into position and subsequently actuating the hammer to upsetthe rivets in the usual manner.

A further object is to provide a novel piston construction responsive to air pressure for feeding the rivets forwardly into a position at the i end of the machine and also reciprocating the hammer for upsetting the rivets.

A still further object is to provide an apparatus.

of this character of simple and practical construction, which is eilicent and reliable in performance and otherwise well adapted for the purposes for which the same is intended.

Other objects and advantages reside in the details of construction and operation as more fully hereinafter described and claimed, reference being had to the accompanying drawings forming part hereof, wherein like numerals refer to like parts throughout, and in which- The figure is a longitudinal sectional view of the riveting machine.

Referring now. to the drawings in detail and wherein for the purpose of illustration I have disclosed a preferred embodiment of the invention, the numeral 5 designates an air gun generally of a type designed particularly for use in upsetting rivets employed in airplane construction, the gun embodying a cylinder 6 having a handle 1 formed at the rear portion thereof and provided with atapered plug 8 at its front end having a bore 8 therein for slidably receiving a hammer I0. q

A hammer head I I is threaded in the front end `of the hammer I for interchangeably inserting different types oi.' hammers for various size rivets.

A coiled spring I2 is mounted in the bore 8 for engaging a flange I3 on the hammer to retract the latter.

A hollow piston Il is slidably mounted in the cylinder 6, the front end of the piston having a bore I5 therein slidably receiving the rear end of the hammer and the rear end of the piston is closed by a plug I6 to form a chamber I1 within the piston.

A piston I8 is formed on the rear end of the hammer I0 and is provided with a working t in the chamber `I1. The chamber I1 is provided with exhaust ports Ila and I1b at opposite sides of piston I 8 and a passage I1c' leads from theexhaust ports to the atmosphere by way of a lateral port 6a in the cylinder 6. The rear end of the cylinder 6 is closed by a cap I9 having a chamber 20 therein and threaded through the cap is an air feed tube 2| having its inner end slidably inserted through a bore 22 and terminating in Athe chamber I1 behind the piston I8.

The tube 2| communicates with a chamber 23 in the handle 1, the chamber having an air intake port 24 inone side thereof and an exhaust 'port 32 at the rear of the chamber controlled by a valve 25 slidably mounted on a rod 26 and yieldably held against a collar 21 fixed to the rod by means of -a *coil spring 28. The rod 26 is slidably mounted transversely of the handle 1 and has its front end projecting forwardly of the handle for engagement by a trigger 29 pivoted to the side of the chamber 6 as indicated at 30. The rear of the chamber 23 is closed by a threaded plug 3| in which the rear end of the valve rod 26 is slidably mounted.

Formed inY the handle 1 forwardly of the chamber '23 is a. chamber 33 with which an air feed passage communicates extending through the handle for connection with a suitable supply of air under'pressure. At the forward end of the chamber 33 is a port 35 in the side of the handle to which a by-pass pipe (not shown) is connected 'leading to the port 24 of the rear chember 23. The port 35 is controlled by a valve 31 secured on the rod 26 and urged intoa closed position by a coil spring 38 mounted on the rod 26 within the chamber 33, the spring 38 being relatively -stronger than the spring 28 so as to the trigger 29 during the rearward movement thereof for actuating 'the valve l2.

As will be observed from an inspection of the drawing, the valve rod 26 projects forwardly of the valve rod I3 so that the former is initially actuated during the rearward movement of the trigger to open the valve 31 and close the valve 26 while a continued rearward movement of the trigger will subsequently actuate the rod I3 for opening the valve 42.

A tube I6 connects the port 41 with the rear end of the cap I9 for supplying air to the chamber 20 therein, the chamber 20 having a passage detailed explanation thereof is not deemed necessary. It will be understood, however, that any improved construction may be provided for operating the piston I4 in a forward and backward reciprocating movement through the medium of air pressure supplied to the cylinder and exhausted therefrom in the usual manner.

A rivet magazine or holder 41 is removably supported on the machine by means of brackets 48 extending upwardly from the cylinder, the rivet holder being constructed of a plurality of spaced parallel rods 49 suitably arranged and open at each end for receiving and discharging the rivets 50 therefrom, the head 5I of the rivets being supported on a pair of the rods 49.

The rods 49 are secured in rigid position to each other by transverse brace members 52 as well as by hangers 53 which rise from the rods and are provided with a slot 54 in one edge thereof adapted for removably supporting the rivet holder on pins 55 carried at the upper ends of the brackets 48.

The brackets 48 are of suitable length to support the rivet holder 41 in a forwardly and downwardly inclined position and the holder is locked in position on the pins 55 of the brackets in any suitable manner.

The upper end of the rivet holder 41 is closed by a cap 51 and prior to placing the cap 51 in position a follower rivet 60 is slidably mounted on the rods behind the rearmost rivet and tothe lower end of the follower rivet 60 is attached a wire or cable 6I extending forwardly under the rivet holder and around a pulley 6'2 and then rearwardly for winding on a spring drum 63 journaled on one of the brackets 48.

The pulley 62 is journaled on a pair of spaced parallel arms 64 extending upwardly from opposite sides of the plug 8, the arms 64 having a shaft 65 supported thereon and on which a rivet feed wheel 66 is rotatably mounted.

The wheel 66 is formed on its peripheral edge with teeth 61 adapted to engage the heads 5l of the rivets as the same drop from the front ends of the rods 49.

A rivet feed tube 68 is mounted under the wheel `.66, the rear end of the tube being curved upwardly behind the wheel as shown at 69 and is split longitudinally as shown at 16 to receive the rivets through the side of the upper end of the tube. The lower end of the split terminates in an upwardly and rearwardly inclined tongue 1I with which the heads of the rivets engage as the latter drop into the tube for properly positioning the rivets for feeding through the curved upper portion 69 of the tube. The tongue 1I also serves as a stop for engaging each lowermost rivet before entering the tube to prevent Jamming thereof at the slot 10.

The tube 68 is pivotally supported intermediate its ends by a member 13 pivotally supported on the shaft 65 and the tube is yieldably urged downwardly at its front end by a coil spring 14 positioned between the tube and the front end of the a'rm 64.

The underside of the front end of the tube 68 is formed with a discharge opening 15 for feeding the rivets to the front end of a resilient clip 16. The rear end of the clip is secured to the plug 8 by a screw 19.

The feed wheel 66 is provided with transverse pins 8| engageable by the front end of a reciproeating step-by-step feed member 83 connected by an eye 85 at its rear end to form a socket for swivelly mounting on a ball 66 at the upper end of the trigger 29.

In the operation of the device air under pressure is admitted through the passage 34 in the handle into the chambers 33 and 39. The spring 38, being stronger than the spring 24. will normally maintain the valve 31 closed until the trigger 29 is initially moved rearwardly. The initial rearward movement of the trigger will slide the rod '26 rearwardly to open the valve 31 admitting airthrough the by-pass pipe 36 into the rear chamber 23, the valve 25 at the same time being moved into its closed position, to prevent escape of air through the discharge port 32.

Air is then admitted to the cylinder or chamber I1 through the tube 2I thereby forcing the piston I8 and hammer I0 forwardly to feed the rivets outwardly of the clip 16 into the usual open- 'ing provided in the work for upsetting the rivets in the usual manner.

Rivets from the holder 41'are fed into the tube 68 through the actuation of the trigger moving the rivet feeding wheel 66 in a step by step movement to discharge the rivets singly into the tube 68.

A spring-pressed ball 9| engages the rivet leeding wheel 66 to prevent idle rotation thereof.

Upon the forward movement of the piston I8 and hammer Ill the hammer head I-I will engage the front end of the tube 68 to pivot the latter upwardly which thereby prevents the next rivet from entering the forward portion of the tube 68 during the riveting action and until the hammer I0 has been retracted by the spring I2.

During the forward movement of the piston I8 and hammer I0 air in the front end of the chamber I1 is exhausted through the bleed passage 92 formed in the hammer. This will enable the piston I8 to move more freely than the piston I4 and accordingly when air is initially admitted into the cylinder I1 the piston I8 will move forwardly until' it strikes the front end of the piston I4 and the pistons I8 and I4 will then move as a unit during reciprocation of the piston I4 when air is subsequently admitted through the tube 45 upon a further rearward movement of the trigger 29 to open the valve 42.

After the hammer I0 has been moved forwardly to eject the rivets through the initial actuation of the trigger 29, the subsequent actuation of the trigger will engage the rod 43 for opening the valve 42 to admit air from the chamber 39 through the pipe 45 into the chamber 26 of the cap I9 where the same enters thecylinder 6 for the actuation of the piston I4 in the usual manner for reciprocably actuating the piston which there- Having described the invention, what is claimed as new is:

1. A pneumatic riveting machine comprising a cylinder, a hollow piston working therein and having a bore in its rear end, a hammer having a. piston integral therewith at its rear end working in the hollow piston, pneumatic means behind the second named piston to maintain the hammer in a. forward position., and including a compressed air tube freely received in the bore 1 of the hollow piston, and means for reciprocably a actuating the hollow piston.

2. An air gunvcomprising a `Cylinder, a hollowpiston working therein, a second piston working in the hollow piston, means for supplying fluid under pressure behind thesecondpiston to con v neet the pistons for uniform mvement'and A111,--

cluding a. compressed air tube projecting-into the rear end of said hollow piston, a hammer at the forward end of the second piston, and means for reciprocably v'actuating' the hollow piston.

3. An air gun comprising a cylinder, interensaxed pistons therein, a hammer intelruiiy` Number Name l Date 141,667 Quick Aug. 12,1873 498,742 Carlinet May 30, 1893 .1.125.471 Szemerey Jan. 19, 1915 1,477,211 Dlesk L..- Dec. 11. 1923 1,503,490 Ditson Aug. 5, 1924 1,758,846` '"Maxson May 13, 1930 2,101,924 Turnquist Dec. 14, 19379"- 2,199,337 Gartin Apr. 30, 1940 2,326,735 Allen Aus. 17, 1943 2,330,052 Henry et nl. Sept. 21, 1943 2,338,157 Allen --.1.1 Jan. 4, 1944 6 formed with one piston, pneumatic actuating means for each Piston, and a sinzie trigger control means for said pneumatic means.

ARTHUR F. KOEHLER.

REFERENCES CITED The following references are of record in the nie of this patent: l

UNITED STATES PATENTS 

